/*
 * Copyright (C) 2007 The Android Open Source Project
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

package com.android.dx.dex.code;

import com.android.dx.rop.code.RegisterSpecList;
import com.android.dx.rop.code.SourcePosition;
import com.android.dx.util.AnnotatedOutput;

/**
 * Base class for instructions which are of a fixed code size and which use
 * {@link InsnFormat} methods to write themselves. This includes most &mdash;
 * but not all &mdash; instructions.
 */
public abstract class FixedSizeInsn extends DalvInsn {

	/**
	 * Constructs an instance. The output address of this instance is initially
	 * unknown ({@code -1}).
	 * <p>
	 * <b>Note:</b> In the unlikely event that an instruction takes absolutely
	 * no registers (e.g., a {@code nop} or a no-argument no-result * static
	 * method call), then the given register list may be passed as
	 * {@link RegisterSpecList#EMPTY}.
	 * </p>
	 * 
	 * @param opcode
	 *            the opcode; one of the constants from {@link Dops}
	 * @param position
	 *            {@code non-null;} source position
	 * @param registers
	 *            {@code non-null;} register list, including a result register
	 *            if appropriate (that is, registers may be either ins or outs)
	 */
	public FixedSizeInsn(Dop opcode, SourcePosition position,
			RegisterSpecList registers) {
		super(opcode, position, registers);
	}

	/** {@inheritDoc} */
	@Override
	public final int codeSize() {
		return getOpcode().getFormat().codeSize();
	}

	/** {@inheritDoc} */
	@Override
	public final void writeTo(AnnotatedOutput out) {
		getOpcode().getFormat().writeTo(out, this);
	}

	/** {@inheritDoc} */
	@Override
	public final DalvInsn withRegisterOffset(int delta) {
		return withRegisters(getRegisters().withOffset(delta));
	}

	/** {@inheritDoc} */
	@Override
	protected final String listingString0(boolean noteIndices) {
		return getOpcode().getFormat().listingString(this, noteIndices);
	}
}
